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Daytona Beach


Human Factors and Behavioral Neurobiology

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During Operation Desert Shield/Storm, A-6 and F-14 aviators aboard USS AMERICA completed daily activity logs and provided subjective measures of fatigue. Aviators flew frequently at night during Desert Storm, but without substantial sleep-related fatigue or problems. A likely contributing factor was the large number of naval aviation assets brought into the combat theater, allowing workload to be shared and activity and rest times to be properly managed. However, raster plots of the data suggest that there may have been an additional contributing factor. The AMERICA travelled eastward from the east coast through seven time zones and became involved in combat shortly after arrival in the Red Sea. This pattern of travel may have given AMERICA's aircrew flying at night a significant advantage over those already operating in the area. If the circadian clocks of AMERICA's aircrew had not fully adapted to local time upon arrival, local night fights were closer to being evening flights on body time. Aircrew may not have been experiencing troughs in their circadian cycles during local night fights, at least for the early part of the war. This would result in a smaller physical challenge to overcome. This situation would likely not hold for aircrew who had been in the region for longer periods, nor would it occur for future conflicts closer to the originating time zone. We recommend the incorporation into battle strategy of information about the circadian phase of combatants (as well as sleep logistics) to help prepare them to fight at suboptimal times.


Pensacola, FL

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AD-A258 146. NAMRL-1375. Dr. Shappell was not affiliated with Embry-Riddle Aeronautical University at the time this report was published.